Compliant hydrodynamic gas lubricated thrust bearings are ideally suited to conditions found in high performance machinery subject to extreme conditions of temperature and speed. However, there is room for improvement in overall load capacity and dynamic stability of the rotor-bearing system at all speeds.
The principal difficulties experienced in known compliant foil thrust bearing systems has been that known bearings exhibit limited foil stiffness resulting in an inability to control axial displacement between the movable and stationary members at elevated speeds. While it is advantageous to minimize the thickness of the foil bearing in order to render the foil sufficiently compliant to conform to the supported member under all conditions, such thin foils exhibit a reduced load-bearing capacity.
Moreover, known gas lubricated thrust bearings do not present a complete solution to the problems of hydrodynamic bearings since there is still a requirement for (a) greater load-carrying capacity (b) a bearing which compensates for misalignment between the movable and stationary elements, and (c) accomodation of thermal distortion of the movable element due to rapid heating of the surface of the movable element nearest the stationary element while the remainder of the movable element remains relatively cool.